(1) Prior to licensure, a Class IV facility must financially assure, with a department approved mechanism, the costs of third party closure, post closure care, and corrective action for known releases at the facility at a time when such activities would be the most expensive.   Such financial assurance must ensure that requisite funds will be available whenever needed.   The amount of the financial assurance must be reviewed, and adjusted if needed, as part of the annual license application renewal process. Allowable mechanisms for financial assurance include:

(a) surety bonds;

(b) trust funds;

(c) letters of credit;

(d) insurance; and

(e) any other department approved mechanism or combination of mechanisms.